On OMAP4, CPU accesses on unmapped addresses are redirected to GPMC by
L3 interconnect. Because of CPU speculative nature, such accesses are possible
which can lead to indirect access to GPMC and if it.s clock is not running,
it can result in hang/abort on the platform.

Above makes access to GPMC unpredictable during the execution, so it's
module mode needs to be kept under hardware control instead of software control.
Since the auto gating is supported for GPMC, there is't a power impact because
of this change.

The issue was un-covered with security middleware running along with HLOS.
In this case GPMC had a valid MMU descriptor on secure side where as HLOS
didn't map the GMPC because it isn't being used.